Information Note on the Court’s case-law 253

July 2021

Akgün v. Turkey - 19699/18

Judgment 20.7.2021 [Section II]

Article 5

Article 5-1-c

Reasonable suspicion

Allegations of active use of encrypted messaging service not used exclusively by a terrorist organisation insufficient to give rise to reasonable suspicion of membership of the organisation: violation

Facts – The applicant, a former police officer who was suspected of membership of the armed terrorist organisation FETÖ/PDY on the sole basis of his alleged use of an encrypted messaging service, since his name had been included the red list of users, was placed in pre-trial detention on 17 October 2016, then charged on 6 June 2017.

Law – Article 5 § 1 (c)

1. The evidence underlying the suspicion, at the time of the applicant’s initial pre-trial detention, that he had committed the offence of membership of an armed terrorist organisation

At the time of the app licant’s initial pre-trial detention the finding that he had used the ByLock messaging system was the only evidence which was provided to justify the suspicion, for the purposes of Article 5 § 1 (c), that he had committed the offence of belonging to FETÖ/P DY.

2. At the time of the initial pre-trial detention, did the national court have sufficient information about the nature of the ByLock messaging system?

The applicant’s alleged criminal activity concerned organised crime. Generally speaking and without prejudice to its subsequent examination of the present case, the Court considered that the use of electronic evidence indicating that an individual availed himself of an encrypted messaging service which had been specially designed for and exclusively used by a criminal organisation for the purposes of that organisation’s internal communication could be a significant instrument in combatting organised crime. In consequence, a suspect could validly be detained at the outset of proceedings on the basis of such evidence, in that it could provide a strong indication that that individual belonged to such an organisation. However, the use of such evidence as the sol e basis underlying a suspicion could pose a number of delicate issues, since, by their nature, the procedure and technologies applied in gathering this evidence were complex and could accordingly reduce the ability of the national courts to establish their authenticity, accuracy and integrity. That being stated, where such evidence formed the sole or exclusive basis of the suspicions against an individual, the national court had to have available sufficient information about the material in question before examining, with prudence, its possible evidential value under domestic law.

In the decisions issued by the High Council of Judges and Prosecutors (HSYK) on 24 and 31 August 2016, in which judges suspected of having links to FETÖ/PDY were dismissed, the HSY K had reached a finding about the nature of ByLock: an encrypted communications system used by the members of that organisation for their internal communications. However, neither of these two HSYK decisions indicated that the encrypted messaging service B yLock was used exclusively by members of FETÖ/PDY with a view to ensuring secret communications within that organisation. In principle, the mere fact of downloading or using a means of encrypted communication or indeed the use of any other method of safegu arding the private nature of exchanged messages could not in itself amount to evidence capable of satisfying an objective observer that an illegal or criminal activity was being engaged in. It was only when the use of an encrypted communication tool was su pported by other evidence about that use, such as, for example, the content of the exchanged messages or the context of such exchanges, that one could speak of evidence that could satisfy an objective observer that there were reasonable grounds to suspect the individual using that communication tool of being a member of a criminal organisation. In addition, the information submitted to the national courts about such use had to be sufficiently precise, so as to enable the relevant court to conclude that the messaging system in question had in reality been intended for use only by members of a criminal organisation. However, that evidence was absent in the present case.

In the light of the HSYK’s decisions, the magistrates’ court had not had sufficient informa tion on the nature of ByLock when ordering the applicant’s initial pre-trial detention in 2016 to conclude that this messaging service was used exclusively by members of the FETÖ/PDY organisation for the purposes of internal communication. Equally, there w as no other factual evidence or information that could have justified the suspicion against the applicant in the pre-trial detention order or the other relevant decisions.

In this connection, it appeared from the order placing the applicant in detention th at the magistrates’ court had simply cited the wording of the Code of Criminal Procedure (CCrP), without taking the trouble to specify what exactly was the “concrete evidence giving rise to a strong suspicion” for the purposes of the relevant provision. Th e vague and general references to the wording of that provision or even to the evidence in the file could not be regarded as sufficient to justify the “reasonableness” of the suspicion on which the detention order was purportedly based, in the absence eith er of a specific assessment of the individual items of evidence in the file, or of any information that could have justified the suspicion against the applicant, or of any other kinds of verifiable material or facts.

Further, the magistrate court’s review of the order for pre-trial detention had not enabled the above defect to be remedied, in that it had dismissed the applicant’s objection against the detention order on the grounds that no inaccuracy had been found. This was also the case with regard to the review conducted by the Constitutional Court, which had dismissed the applicant’s individual application by a mere reference to the bill of indictment lodged on 6 June 2017 – long after the applicant’s initial placement in detention – as justification for the suspicion against him when he was initially detained.

3. Had there been sufficient evidence to justify a reasonable suspicion that the applicant had used ByLock?

In view of the conclusion reached by the Court above, there was in principle no need to address this last question. However, given its importance in the present case, the Court decided to assess this issue.

It appeared from the case file that the only evid ence underlying the suspicion that the applicant had committed the offence of membership of FETÖ/PDY was the prosecution service’s finding that his name was on the red list of ByLock users, which allegedly indicated the applicant was an active user of this communication tool. However, this was a mere conclusion, devoid of any indication or explanation regarding the basis on which the authorities had reached it, and especially regarding the data used for that purpose. The relevant document did not include th e underlying data on which it was based or provide information about the manner in which this data had been gathered. The national courts had therefore based their decisions on this one document, of one page in length, which was undated and anonymous.

The document concluding that the applicant had used ByLock did not as such specify or set out any illegal activity on the applicant’s part, in that it did not identify either the dates of this presumed activity or its frequency, and did not contain any additio nal related details. Furthermore, neither this document nor the pre-trial detention order explained how this presumed activity by the applicant indicated his membership of a terrorist organisation.

In consequence, the Court considered that in the absence o f other evidence or information, the document in question, stating merely that the applicant was a user of ByLock, could not, in itself, demonstrate that there were reasonable suspicions capable of satisfying an objective observer that he had indeed used B yLock in a manner that could amount to the alleged offences.

4. Conclusion

Given those considerations, the Government had been unable to show that at the date on which the applicant was placed in pre-trial detention the evidence available to the magistra te’s court had met the standard of “reasonable suspicion” that was required by Article 5 of the Convention, such as to satisfy an objective observer that he might have committed the offences for which he had been detained.

As to the concept of the “reasona bleness” of the suspicions on which the detention was based during the state of emergency, the present complaint did not strictly concern a measure taken to derogate from the Convention during the state of emergency. The magistrates’ court ordered the appl icant’s placement in pre-trial detention for membership of a terrorist organisation in application of Article 100 of the CCrR, a provision that was not amended during the state of emergency. The applicant’s detention had therefore been ordered on the basis of legislation which was in force prior to the declaration of the state of emergency, and which, moreover, was still applicable.

The difficulties facing Turkey in the aftermath of the attempted military coup were undoubtedly a contextual factor which the Court had fully to take into account in interpreting and applying Article 5 of the Convention. This did not mean, however, that the authorities had carte blanche to order an individual’s detention during the state of emergency without any verifiable eviden ce or information or without a sufficient factual basis satisfying the minimum requirements of Article 5 § 1 (c) regarding the reasonableness of a suspicion. The “reasonableness” of the suspicion on which deprivation of liberty had to be based formed an es sential part of the safeguard laid down in Article 5 § 1 (c) of the Convention. In such circumstances, the measure in issue could not be said to have been strictly required by the exigencies of the situation. To conclude otherwise would negate the minimum requirements of Article 5 § 1 (c) regarding the reasonableness of a suspicion justifying deprivation of liberty and would defeat the purpose of Article 5 of the Convention.

It followed that there had not been a reasonable suspicion, at the time of the app licant’s initial pre-trial detention, that he had committed an offence.

Conclusion : violation (six votes to one).

The Court also concluded, by six votes to one, that there had been a violation of Article 5 § 3 with regard to the alleged lack of relevant re asons to justify pre-trial detention in the absence of reasonable grounds for suspecting the applicant; and a violation of Article 5 § 4, since neither the applicant nor his lawyer had had sufficient knowledge of the content of the red list of ByLock users , available exclusively to the prosecution, which had been of crucial importance for challenging the detention in issue.

Article 41: EUR 12,000 in respect of non-pecuniary damage.

© Council of Europe/European Court of Human Rights This summary by the Regi stry does not bind the Court.

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